What is a rudra veena?

The rudra veena, called the bin or been in North India, is a plucked stick zither of Hindustani music. A hollow tube of bamboo or teak carries the frets and strings, with two calabash gourd resonators beneath. It has four melody strings and three chikari drone strings. The Met notes that it appears routinely in ragamala paintings and is closely associated with dhrupad.